Abstract
The Melody Triangle is a smartphone application for Android that lets users easily create musical patterns and textures. The user creates melodies by specifying positions within a triangle, and these positions correspond to the information theoretic properties of generated musical sequences. A model of human expectation and surprise in the perception of music, information dynamics, is used to 'map out' a musical generative system's parameter space, in this case Markov chains. This enables a user to explore the possibilities afforded by Markov chains, not by directly selecting their parameters, but by specifying the subjective predictability of the output sequence. As users of the app find melodies and patterns they like, they are encouraged to press a 'like' button, where their setting are uploaded to our servers for analysis. Collecting the 'liked' settings of many users worldwide will allow us to elicit trends and commonalities in aesthetic preferences across users of the app, and to investigate how these might relate to the informationdynamic model of human expectation and surprise. We outline some of the relevant ideas from information dynamics and how the Melody Triangle is defined in terms of these. We then describe the Melody Triangle mobile application, how it is being used to collect research data and how the collected data will be evaluated.